Corsair’s H115i Pro and H150i Pro CPU coolers reviewed

Even after a company introduces a great and enduring product, the constantly-blowing winds of market demands eventually require a change in tack. When this demand isn’t carefully handled, a company risks ruining the very things that made a product successful to begin with. Sometimes drastic changes work, as Apple’s radical re-imagining of the iPhone user experience with the iPhone X proves. Sometimes they don’t, as with the mixed reception of Apple’s radical re-imagining of the 2016 MacBook Pro.

Corsair has arguably been the company most responsible for ushering in the closed-loop liquid-cooled era of enthusiast PC hardware. The H60, H80, and H100, introduced in 2011, likely marked the crossover point where an all-in-one liquid cooler became an enduring and attainable option for enthusiasts versus a monster tower-style air cooler. The company later expanded its lineup with the H105, H110, and a variety of Corsair Link-compatible i-series versions of those coolers, and it sourced those products from Asetek (in GTX guises) and CoolIT Systems (with the GT tag line) alike. I’ve long used versions of these coolers on my personal systems and test benches alike thanks to their easy-to-use mounting systems, low stress on motherboards, and high performance.

In light of that storied history, Corsair’s H115i Pro and H150i Pro coolers have a lot riding on their shoulders as they launch today. The 280-mm H115i Pro is an evolution of Corsair’s existing H110i GTX, while the H150i Pro is the company’s first 360-mm closed-loop cooler ever. In a world where 16 or 18 cores can be found under the heat spreaders of enthusiast CPUs, a 360-mm radiator isn’t as insane an idea as it might sound, and several other manufacturers have already beat Corsair to the punch in offering such a radiator size.

Performance concerns aside, enthusiast PCs are more and more a statement of style, too. The sedate RGB LED lighting on today’s H100i GT, H100i GTX, H110i GT, and H110i GTX boasts the same 16.7 million potential shades as every other RGB LED component, but it could be outshined by the brighter and more numerous RGB LEDs elsewhere in a fully-illuminated build.

To more boldly proclaim a builder’s Corsair allegiance to the world, the H115i Pro and H150i Pro both start with a redesigned pump head that’s more stylish and more premium-looking to my eye than past Corsair coolers—not an easy task. The basic pump-head design starts with a glossy black plastic Corsair emblem ringed with aluminum. RGB LEDs shine through the Corsair logo and through the translucent plastic that sits between the aluminum band and the plastic emblem. Another layer of frosted plastic sandwiched between the aluminum band and the black plastic lower housing of the pump gives the RGB LEDs inside another place to shine.

Flipping the pump head over gives us a good look at the circular, brushed-copper cold plate common to both of these coolers. A similar cold plate has served as the business end of many Corsair coolers for years, and the company clearly isn’t messing with what works here. What is new here is the four-peg twist-and-lock system that holds cooler brackets in place.

If the pump head of the H115i Pro and H150i Pro is bolder than that of past Corsair coolers, the radiator for these heatsinks is more subdued than ever. A simple chrome Corsair logo replaces the graphite-colored accent bar that used to run the full length of the radiator on older Corsair all-in-ones, and the end tanks of these radiators have been entirely wrapped in a blocky matte-black shell. Most people aren’t looking to the radiator of an all-in-one cooler as a major point of style for their systems, but I personally preferred the distinctive look of past Corsair all-in-ones to the more restrained style of the Pro-series coolers. To each their own.

Brains and brawn

Both the H115i Pro and H150i Pro have a Micro-USB port onboard to let them talk with Corsair’s Link software for RGB LED, fan-speed, and pump-speed controls. They also have onboard fan controllers so that a builder can bypass a system’s motherboard fan-control utilities in favor of Corsair Link’s built-in capabilities. The included Micro-USB cable connects to an internal USB 2.0 header available on practically every motherboard.

Once the cooler is connected to the motherboard, Corsair Link can set three pump speeds and configure the cooler’s onboard lighting using a variety of prebaked animation settings. Link still can’t talk to other RGB LED sync utilities, though, so truly RGB LED-obsessed builders will need to content themselves with finding the best possible complement of lighting and animations that matches up with other LED-illuminated components—or stick with RGB LED components from Corsair only.

Even without RGB LED fan control, the Hydro Pro-series pump head sprouts a fair bit of cabling so that the cooler can get power and connect to any accompanying fans. The cooler needs a SATA power connection to run its pump, and it also has a three-pin header for communicating pump speed to the motherboard.

This mass of permanent cabling is one of my few minor gripes about the design of Corsair’s Hydro i-series coolers in general, and I’m a tad disappointed that it hasn’t been cleaned up in the Hydro Pro series. Fitting sockets for optional cables to the pump head would increase its size and profile, but a socketed approach would also satisfy builders seeking the cleanest-cabled systems possible. At least for fan control, I believe Corsair could even be better served by accepting that most modern motherboards already have perfectly competent fan-control systems or even utilities that are superior to its own offerings. Regardless of my gripes, these twin four-pin fan headers are still there for those who want them, and when paired with Corsair Link, they can actually stop the fans on the H115i Pro and H150i Pro when the system is idle. The cooler will kick on the fans when coolant temperatures exceed 40° C.

Magnetic levitation comes standard

My single biggest stumbling block with Corsair’s past liquid coolers has been the balance between noise levels and the performance of its included fans. The company’s past 120-mm and 140-mm fans emphasized performance over noise levels, and a pair of those fans creates an intolerable racket to my ear at full tilt (as they would need to run while cooling an overclocked CPU, for example). The H115i Pro and H150i Pro take a different approach. The boxes for these coolers call them “low-noise” coolers instead of “extreme performance” models, the tag line attached to many of the company’s existing all-in-ones.

To fulfill that mission, Corsair includes a welcome functional change on top of these coolers’ bolder RGB LED accents: versions of its superb ML-series fans now come in the box with both of these coolers. I first went in depth with the ML120 Pro RGB trio earlier this year, and I came away thoroughly impressed with them. Even with a relatively low top speed, the ML-series proved more than capable of sticking with or beating out much faster-spinning fans while turning in lower noise levels across the board.

To keep the prices of these coolers reasonable, Corsair stripped the ML-series fans back to their basics. Both the H150i Pro’s ML120 fans and the H115i Pro’s ML140 fans use plain gray rotors and black PBT frames without any kind of rubber corner padding or other gimmicks. The 120-mm fans on board the H150i have a PWM range of 400 RPM to 1600 RPM, as the ML120 Pro RGBs do, and the H115i Pro’s 140-mm fans range from 400 RPM to 1200 RPM. I don’t lament the loss of RGB LEDs or rubber pads on these fans so long as their superb noise character remains untouched.

Puzzling out installation possibilities

Many past Corsair coolers used a stock Asetek mounting ring design with several interlocking teeth and slots ringing the cold plate. That system worked well enough in the rare instances where builders needed to swap mounting brackets (like one has to do with the included bracket for AMD’s Ryzen Threadripper CPUs), but even though it’s designed for easy bracket switches, I had to use an eyebrow-raising amount of force to pop off the stock Intel mounting ring on one of the Corsair H115i coolers in the TR labs. The new four-peg system on the H115i Pro and H150i Pro lets the bracket come free with far less force, so it’s a lot more user-friendly.

Builders of AMD systems will benefit the most from this new system. Corsair pre-installs an Intel mounting bracket on the coolers from the factory, so builders pledging allegiance to the blue team don’t need to bother with a bracket swap. The downside of the new four-peg system is that only folks building Socket AM4 systems will be able to take advantage of the Hydro Pro-series duo out of the box. Corsair includes full mounting hardware for use with Socket AM4’s mounting ears with the cooler, so installing either heatsink on any non-Threadripper system should be a snap.

The problem for Threadripper builders is that the Asetek-compatible bracket that AMD includes in the box with those chips won’t fit on the new Corsair mounting pegs at all. Corsair will almost certainly offer a Socket TR4 bracket to those Hydro Pro-series buyers who want to mate their coolers with a Threadripper CPU, but the wait involved with getting one of those brackets is an annoying side effect of buying a more niche CPU than AM4 or LGA 1151 fare.

Thanks to Intel’s perennial popularity, builders with any LGA 115x motherboard or LGA 20xx socket will enjoy frustration-free compatibility from the Hydro Pro coolers. Corsair includes a backplate and mounting bolts for LGA 115x systems and mounting bolts for the integrated cooler-mounting system of LGA 20xx motherboards.

I’d devote more attention to actually installing the H150i Pro and H115i Pro on our test system here, but installing these coolers is really so simple that it doesn’t merit much explanation. On Intel LGA 115x systems, one simply screws four double-ended bolts into the plastic backplate, sandwiching the motherboard with the four cooler-mounting holes present on those mobos. LGA 2011 and LGA 2066 systems don’t even need a mounting bracket—the four included mounting bolts for those sockets screw right into the integrated heatsink mounting system on those motherboards.

Once the base mounting system is in place, one only has to situate the cooler’s pump head on top of the CPU before securing it with four large cap nuts. Corsair’s hardware is refreshingly finger-friendly, and I only needed a screwdriver to deliver the final twist on the cap nuts. With installation complete, we can see how these coolers perform.

Our testing methods

We used the following configuration for our test system:

Processor / Intel Core i9-7980XE
Motherboard / Asus Prime X299 Deluxe
Memory / 32 GB (4x8GB) G.Skill Trident Z DDR4-3600
Graphics card / MSI GeForce GTX 1070 Gaming Z
Storage / Samsung 960 Pro 512 GB
Power supply / Seasonic Prime Platinum 1000 W
OS / Windows 10 Pro

Our thanks to Intel, G.Skill, MSI, Corsair, and AMD, among other vendors, for helping us outfit our test rigs with some of the best hardware available. Our thanks as well to Corsair for providing the coolers we’re reviewing today.

Although this is a heatsink review, running our usual Prime95 Small FFTs load on a CPU with AVX-512 support and lots of cores will overwhelm any cooler. For testing overclocked stability of Intel’s many-core CPUs with exceptionally wide AVX units, I’ve instead taken to running the Classroom Blender benchmark available as part of Blender’s standard benchmark scenes. Blender still fires up CPUs’ AVX units plenty hard, as we’ll see.

Stock-clocked cooling performance

To test stock-clocked performance of these heatsinks, I normalized fan speeds to 1000 RPM across all of our coolers and ran the Classroom benchmark three times in close succession while noting the maximum CPU package temperature reached over the course of that test.

At stock speeds, all three of these coolers are more than up to the task of holding the Core i9-7980XE in check. Though the H150i Pro takes a narrow lead, a three-degree-C spread simply isn’t worth getting worked up over. Let’s turn to overclocking to see if we can’t tease out larger differences between this trio of heatsinks.

Overclocked cooling performance

To really give these CPU coolers a workout, I overclocked our Core i9-7980XE’s 18 cores to 4.3 GHz across the entire chip. I achieved Blender stability with this setup at an indicated 1.1675 V using adaptive voltage offsets. I then ran each cooler’s included fans at the maximum speed possible using the “full speed” fan setting on our Asus motherboard test bed.

Even without Prime95, the i9-7980XE proves a potent challenge for all three of these coolers. Admittedly, all three of these heatsinks are running much closer to the i9-7980XE’s observed 105° C throttling temperature than we might like, but even an overclock doesn’t reveal major differences in cooling effectiveness among old and new here. That result suggests something else (ahem, TIM) might be limiting thermal transfer from the i9-7980XE into our liquid coolers. One might still need to delid and re-paste a Core i9-7980XE for the best overclocking potential, but for those unconcerned with high operating temperatures in normal use, the Hydro Pro coolers will keep the chip within normal operating ranges.

Noise levels

To test the noise levels of these coolers, I measured dBA levels at a distance of one meter from our test bench using the Faber Acoustical SoundMeter application. The CPU cooler was the only source of noise from the system.

In absolute terms, the Hydro Pro series coolers register ever so slightly quieter than the H110i GTX does at idle, but they become just a bit louder than the older cooler does at 1000 RPM. Crank up the fans to full speed, and the lower maximum RPMs of the Hydro Pros’ ML fans translate into much lower noise levels than the 2400-RPM max of the SP140Ls aboard the H110i GTX. What’s surprising is that despite that huge increase in noise, the H110i GTX doesn’t actually offer better performance than the Hydro Pro-series coolers do at their much quieter maximum speeds. That alone is a huge win for Corsair’s latest and greatest.

Absolute noise levels are only one measure of a cooler’s agreeableness to the ear. Subjective character is just as important. Happily, the ML120 and ML140 fans included with these coolers perform just as well by that measure as they do in our absolute measurements. At 1000 RPM, all of the coolers easily fade into the background, although the SP140L fans on the H110i GTX have a slight ticking sound that can be picked out if one is in a quiet space. At full speed, however, there’s no contest. The H115i Pro’s ML120 fans sound mostly like air moving, with a vanishingly slight high-midrange character to their sound that’s easily ignorable. The ML140s offer a quiet whoosh with an equally slight low tone to the ear, and it’s equally unobjectionable. Compared to the ML duo, the SP140Ls produce an oppressive roar that will be impossible to ignore without an extremely loud sound system or closed headphones.

As liquid coolers, all three of these heatsinks will have a suggestion of pump noise at idle. Despite their ostensibly lower overall noise levels, the lack of perceptible fan noise from the ML120s and ML140s at idle seems to reveal this pump noise more than the H110i’s pair of SP140Ls do. At their maximum pump speeds, as I tested them here, the Hydro Pro coolers have a much more prominent high-pitched whine than the H110i GTX does. I expect this whine will be dulled by a case, but sensitive ears might still be annoyed by it. For those that do find the whine troublesome, Corsair Link’s Quiet and Balanced pump speeds do kill the worst of it on the Hydro Pro coolers, but one has to manually fiddle with that option every time they anticipate heavy CPU loads. It’d be nice if Corsair Link could automatically switch among the three pump-speed profiles depending on system load and CPU temperatures, given its detailed system-monitoring capabilities.

Conclusions

Corsair’s H115i Pro and H150i Pro liquid coolers avoid the pitfalls of messing with success. When Corsair whipped up this new generation of heatsinks, it only improved the things we already liked about past Hydro Series coolers. The restyled and boldly-illuminated pump head on these all-in-ones will look great with any system, the performance of both coolers is on par with past Corsair heatsinks, and both of these coolers deliver their performance while remaining plenty quiet. At full speed, the performance-per-decibel of the H150i Pro and H115i Pro is outstanding.